TW202309559A - Optical filter - Google Patents

Abstract

One embodiment of the optical filter according to the present invention is provided with a transparent base material that has a first main surface, and a first light absorption layer that is arranged on the first main surface side of the transparent base material; the first light absorption layer contains a near-infrared absorbing dye and an inorganic material; and the near-infrared absorbing dye has a maximum absorption wavelength at a wavelength of 650 nm to 760 nm, while having a molecular weight of 2,000 or less.

Description

filter

The present invention relates to an optical filter.

An imaging device such as a digital camera or a digital video camera has a solid-state imaging device (CCD (Charge Coupled Device, Charge Coupled Device), CMOS (Complementary Metal Oxide Semiconductor, Complementary Metal Oxide Semiconductor), etc.) to sense people or scenery. The solid-state imaging device has a stronger sensitivity to infrared light than human vision. Therefore, in order to make the image obtained by the solid-state imaging device close to the visual sensitivity of human beings, filters such as near-infrared cut filters are further provided in the imaging device.

Generally speaking, such an optical filter is formed by disposing a light absorbing layer that shields near infrared rays on a transparent substrate. For example, Patent Document 1 discloses a near-infrared cut filter comprising a laminate having a resin layer on at least one side of a glass substrate, and the resin layer contains a pigment as a near-infrared absorber. prior art literature patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2012-103340

[Problem to be solved by the invention]

In recent years, especially with the improvement of the performance of the imaging device mounted in the smartphone, the filter which has the excellent light resistance is requested|required.

However, in the near-infrared cut filter of Patent Document 1, the pigment as a near-infrared absorbing agent is contained in the resin layer, so the pigment may react with hydroxyl groups in the resin due to sunlight or indoor light, and photooxidation may occur. deteriorating. Therefore, the light resistance of the near-infrared cut filter of Patent Document 1 may not be sufficient.

An object of an aspect of the present invention is to provide an optical filter having excellent light resistance and near-infrared shielding properties. [Technical means to solve the problem]

An aspect of the optical filter of the present invention includes a transparent substrate having a first main surface, and a first light-absorbing layer provided on the first main surface side of the transparent substrate, and the first light-absorbing layer includes A near-infrared-absorbing dye, and an inorganic material, wherein the near-infrared-absorbing dye has a maximum absorption wavelength at a wavelength of 650 nm to 760 nm, and has a molecular weight of 2000 or less. [Effect of Invention]

An aspect of the present invention can provide an optical filter having excellent light resistance and near-infrared shielding properties.

Embodiments of the present invention will be described in detail below.

An optical filter according to one embodiment will be described. Fig. 1 is a schematic cross-sectional view of an optical filter according to an embodiment of the present invention. As shown in FIG. 1 , the optical filter 10 has a transparent substrate 1 and a first light-absorbing layer 2 provided on one principal surface (first principal surface) of the transparent substrate 1 .

[Transparent substrate] The transparent substrate 1 may contain any material as long as it is transparent to visible light (high transmittance). For example, the transparent substrate 1 may contain glass (whiteboard glass, near-infrared absorption glass, etc.), or resin.

[1st light absorbing layer] The first light-absorbing layer 2 is a layer that absorbs near-infrared rays. The first light-absorbing layer 2 is a layer containing a near-infrared-absorbing dye (A) that absorbs near-infrared rays and an inorganic material (B). As a typical example, the near-infrared-absorbing dye (A) is dispersed in an inorganic material (B). layer. In other words, it is a layer in which the inorganic material (B) and the near-infrared absorbing dye (A) are mixed. The infrared absorbing pigment (A) may be uniformly dispersed in the inorganic material (B), or the concentration may vary in the direction perpendicular to the first main surface of the transparent substrate 1 (thickness direction of the transparent substrate 1).

(Near-infrared-absorbing dye) As long as the near-infrared-absorbing dye (A) is a near-infrared-absorbing dye having a maximum absorption wavelength (hereinafter referred to as "λ _max ") in the wavelength range of 650 nm to 760 nm and a molecular weight of 2000 or less, There are no special restrictions. Furthermore, λ _max has an absorption peak having an absorption peak (hereinafter referred to as "absorption peak of λ _max "). The absorption curve of the near-infrared absorbing dye (A) is preferably not only λ _max in the wavelength region of 650 nm to 760 nm, but also has less absorption in the visible light region, and the slope of the visible light side of the absorption peak of λ _max is steep. Furthermore, the absorption peak of λ _max preferably has a gentle slope on the long wavelength side.

Regarding the _λmax of the near-infrared-absorbing dye (A), a solution obtained by dissolving the near-infrared-absorbing dye (A) in dichloromethane can be used, for example, using a UV-Vis-NIR spectrophotometer (manufactured by JASCO Corporation, model: V770) is measured to obtain an absorption curve in the wavelength range of 400 nm to 850 nm, and the λ _max of the above-mentioned near-infrared absorbing dye (A) is detected from the absorption curve. In this specification, unless otherwise specified, the measurement of the absorption curve is conveniently performed at an incident angle of 0°.

The near-infrared absorbing pigment (A) has a maximum absorption wavelength in the wavelength region of 650 nm to 760 nm, thereby imparting an excellent ability to absorb light in the near-infrared wavelength region (700 nm to 1100 nm) to the filter 10 . In addition, the molecular weight of the near-infrared-absorbing dye (A) is 2000 or less, whereby the near-infrared-absorbing dye (A) can be formed on a transparent substrate at low temperature. Therefore, thermal deterioration of the near-infrared absorbing dye (A) can be suppressed, and desired near-infrared absorbing characteristics can be obtained in the optical filter 10 .

Examples of the near-infrared absorbing dye (A) include cyanine-based compounds, phthalocyanine-based compounds, naphthalocyanine-based compounds, dithiol metal complex-based compounds, diimonium-based compounds, polymethine-based Compounds, phthalide compounds, naphthoquinone-based compounds, anthraquinone-based compounds, indophenol-based compounds, squarylium-based compounds, and the like.

Among them, squarylium-based compounds, cyanine-based compounds, and phthalocyanine-based compounds are more preferable, and squarylium-based compounds are particularly preferable. Regarding the near-infrared-absorbing dye (A) containing a squarylium-based compound, in the above-mentioned absorption curve, the absorption in the visible light region is small, the absorption peak of λ _max has a steep slope on the visible light side, and the storage stability and light sensitivity are relatively low. The stability is high, so it is preferable. Regarding the near-infrared-absorbing pigment (A) containing a cyanine-based compound, in the above-mentioned absorption curve, the absorption in the visible light region is small, and the absorption rate of light on the long-wavelength side in the wavelength region near λ _max is high, so it is preferable. . In addition, cyanine-based compounds are known to be conventionally used as pigments for recording colors in CD-R (Compact Disc-Recordable, CD-recordable) and the like, and are known to be inexpensive and to ensure long-term stability by forming a salt. The near-infrared-absorbing dye (A) containing a phthalocyanine-based compound is preferable because it is excellent in heat resistance and weather resistance.

The near-infrared-absorbing dye (A) that is a squarylium-based compound specifically includes at least one selected from squarylium-based compounds represented by the following formula (F1). In this specification, the compound represented by formula (F1) is called compound (F1). The same is true for other compounds.

Compound (F1) is a squarylium-based compound having a structure in which a benzene ring is bonded to the left and right of the squarylium skeleton, and a nitrogen atom is bonded to the 4-position of the benzene ring, and a structure containing the nitrogen is formed. The above-mentioned compound (F1) is a compound having a light-absorbing property as the above-mentioned near-infrared absorbing dye (A) for a saturated heterocyclic ring of atoms. Regarding the compound (F1), the substituents of the benzene ring can be appropriately adjusted within the following ranges according to other required characteristics, such as improving the solvent used when forming the first light-absorbing layer (hereinafter, sometimes referred to as is the solubility in the "main solvent") or inorganic material (B).

[chemical 1]

The symbols in formula (F1) are as follows. R ⁴ and R ⁶ independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group with 1 to 20 carbons, an alkoxy group with 1 to 20 carbons, an acyloxy group with 1 to 10 carbons, an acyloxy group with 6 to 20 carbons, 11 aryl groups, alkaryl groups with 7 to 18 carbons which may have substituents and may have an oxygen atom between carbon atoms, -NR ⁷ R ⁸ (R ⁷ and R ⁸ each independently represent a hydrogen atom, carbon number 1 ~20 alkyl groups, -C(=O) ^-R9 ( ^R9 is a hydrogen atom, a halogen atom, a hydroxyl group, may have a substituent and may contain an unsaturated bond between carbon atoms, an oxygen atom, a saturated or unsaturated ring Hydrocarbon group with 1 to 25 carbon atoms in the structure), -NHR ¹⁰ , or -SO ₂ -R ¹⁰ (R ¹⁰ is one or more hydrogen atoms, which can be replaced by halogen atoms, hydroxyl, carboxyl, sulfo, or cyano And may contain unsaturated bonds between carbon atoms, oxygen atoms, hydrocarbon groups with 1 to 25 carbon atoms in saturated or unsaturated ring structures)), or groups represented by the following formula (S) (R ⁴¹ , R ⁴² independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 10 carbons or an alkoxy group having 1 to 10 carbons, and k is 2 or 3).

R ¹與R ²、R ²與R ⁵、及R ¹與R ³可相互連結而與氮原子一起形成員數為5或6之各個雜環A、雜環B、及雜環C。 [Chem 2]

R ¹ and R ² , R ² and R ⁵ , and R ¹ and R ³ may be linked together to form heterocycle A, heterocycle B, and heterocycle C each having 5 or 6 members together with a nitrogen atom.

Regarding R ¹ and R ² when forming the heterocycle A, as the divalent group -Q- formed by bonding them, it means that the hydrogen atom can pass through an alkyl group with 1 to 6 carbons, or an aromatic group with 6 to 10 carbons. or an alkylene group substituted with an acyloxy group having 1 to 10 carbon atoms which may have a substituent, or an alkyleneoxy group.

Regarding R ² and R ⁵ when forming the heterocycle B, and R ¹ and R ³ when forming the heterocycle C, each of the divalent groups -X ¹ -Y ¹ - and -X ² formed by bonding them -Y ² -(the sides bonded to nitrogen are X ¹ and X ² ), X ¹ and X ² are groups represented by the following formula (1x) or (2x) respectively, Y ¹ and Y ² are selected from A group represented by any one of the following formulas (1y) to (5y). When X ¹ and X ² are each a group represented by the following formula (2x), each of Y ¹ and Y ² may be a single bond.

[Chem 3]

In the formula (1x), the four Zs each independently represent a hydrogen atom, a hydroxyl group, an alkyl or alkoxy group with 1 to 6 carbons, or -NR ²⁸ R ²⁹ (R ²⁸ and R ²⁹ each independently represent a hydrogen atom or an alkyl group with 1 to 20 carbon atoms). R ²¹ to R ²⁶ independently represent a hydrogen atom, an alkyl group with 1 to 6 carbons, or an aryl group with 6 to 10 carbons, and R ²⁷ represents an alkyl group with 1 to 6 carbons or an aryl group with 6 to 10 carbons .

R ⁷ , R ⁸ , R ⁹ , R ⁴ , R ⁶ , R ²¹ to R ²⁷ , R ¹ to R ³ when not forming a heterocycle, and R ⁵ may be bonded to any other of them to form 5 member ring or 6 member ring. R ²¹ and R ²⁶ , and R ²¹ and R ²⁷ may be directly bonded.

R ¹ and R ² when not forming a heterocycle each independently represent a hydrogen atom, an optionally substituted alkyl or allyl group having 1 to 6 carbons, or an aryl or alkaryl group having 6 to 11 carbons. R ³ and R ⁵ when not forming a heterocycle each independently represent a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 6 carbon atoms.

Hereinafter, the heterocyclic ring A may also be simply referred to as the ring A. The same applies to heterocycle B and heterocycle C.

In the compound (F1), R ⁴ and R ⁶ each independently represent the above-mentioned atoms or groups. The halogen atom may, for example, be a fluorine atom, a chlorine atom or a bromine atom. The alkyl group may be any of linear, branched and cyclic. R ⁴ and R ⁶ are preferably a combination in which either one is a hydrogen atom and the other is -NR ⁷ R ⁸ .

In the case where compound (F1) has only ring A, only ring B and ring C, and ring A to ring C among ring A to ring C, -NR ⁷ R ⁸ can be introduced into any of R ⁴ and R ⁶ in one. When the compound (F1) has only ring B, only ring A and ring B respectively, -NR ⁷ R ⁸ is preferably introduced into R ⁴ . Likewise, when having only ring C, only ring A, and ring C, respectively, -NR ⁷ R ⁸ is preferably introduced into R ⁶ .

-NR ⁷ R ⁸ is preferably -NHC(=O)-R ⁹ from the viewpoint of solubility in the main solvent or the inorganic material (B). R ⁹ is preferably an optionally substituted alkyl group having 1 to 20 carbon atoms, an optionally substituted aryl group having 6 to 10 carbon atoms, or an optionally substituted group that may have an oxygen atom between carbon atoms. An alkaryl group having 7 to 18 carbon atoms. As the substituent, a fluorine atom, an alkyl group having 1 to 6 carbons, a fluoroalkyl group having 1 to 6 carbons, an alkoxy group having 1 to 6 carbons, an acyloxy group having 1 to 6 carbons, etc. .

Among these, R ⁹ is preferably a group selected from the following groups: linear, branched, and cyclic alkyl groups with 1 to 17 carbon atoms which may be substituted by fluorine atoms; A fluoroalkyl group with 1 to 6 carbons and/or a phenyl group substituted with an alkoxy group with 1 to 6 carbons; Alkaryl of an alkyl group having 1 to 6 carbons and/or a phenyl group which may be substituted with an alkoxy group having 1 to 6 carbons.

In compound (F1), ring A, ring B, and ring C with 5 or 6 members formed by R ¹ and R ² , R ² and R ⁵ , and R ¹ and R ³ being linked to each other, as long as at least Any one of them may be formed, and two or three may be formed.

R ¹ and R ² when not forming a ring each independently represent a hydrogen atom, an optionally substituted alkyl or allyl group having 1 to 6 carbons, or an aryl or alkaryl group having 6 to 11 carbons. The alkyl group may be any of linear, branched and cyclic. The substituent may, for example, be a hydroxyl group, an alkoxy group having 1 to 3 carbon atoms, or an acyloxy group having 1 to 3 carbon atoms. R ³ and R ⁵ when not forming a ring each independently represent a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 6 carbon atoms. Among these, R ¹ , R ² , R ³ , and R ⁵ are preferably an alkyl group having 1 to 3 carbons from the viewpoint of solubility in the main solvent or the inorganic material (B), Especially preferred are methyl and 2-propyl.

In addition, in compound (F1), the groups R ¹ to R ⁶ of the benzene rings bonded to the left and right sides of the squarylium skeleton may be different from left to right, and preferably left to right are the same.

Furthermore, the compound (F1) includes a compound (F1-1) represented by the formula (F1-1) having a resonance structure of the structure represented by the above general formula (F1).

[chemical 4]

Wherein, the symbols in the formula (F1-1) are the same as those specified in the above formula (F1).

As the compound (F1), more specifically, a compound represented by the following formula (F11) having only ring B as a ring structure, a compound represented by the following formula (F12) having only ring A as a ring structure A compound represented by the following formula (F13) having two ring structures of ring B and ring C. In addition, the compound represented by the following formula (F11) is the same compound as the compound having only ring C as a ring structure in compound (F1), and R ⁶ is -NR ⁷ R ⁸ . Also, the compound represented by the following formula (F11) and the compound represented by the following formula (F13) are compounds described in US Patent No. 5,543,086.

[chemical 5]

[chemical 6]

[chemical 7]

The symbols in the formulas (F11) to (F13) are the same as those specified in the above formula (F1), and the preferred aspects are also the same.

In the compound (F11), X ¹ is preferably an ethylylene group in which the hydrogen atom represented by the above (2x) may be substituted with an alkyl group having 1 to 6 carbons or an aryl group having 6 to 10 carbons. In this case, the substituent is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group. As X ¹ , specifically, -(CH ₂ ) ₂ -, -CH ₂ -C(CH ₃ ) ₂ -, -CH(CH ₃ )-C(CH ₃ ) ₂ -, -C( CH ₃ ) ₂ -C(CH ₃ ) ₂ -etc. As -NR ⁷ R ⁸ in compound (F11), preferably -NH-C(=O)-CH ₃ , -NH-C(=O)-C ₆ H ₁₃ , -NH-C(=O) -C ₆ H ₅ , -NH-C(=O)-CH(C ₂ H ₅ )-C ₄ H ₉ , -NH-C(=O)-C(CH ₃ ) ₂ -C ₂ H ₅ ,- NH-C(=O)-C(CH ₃ ) ₂ -C ₃ H ₇ , -NH-C(=O)-C(CH ₃ ) ₂ -(CH ₂ ) ₃ -OC ₆ H ₃ (CH ₃ ) ₂ etc.

As the compound (F11), for example, the following formula (F11-1), formula (F11-2), formula (F11-3), formula (F11-4), formula (F11-5), formula ( F11-6), compounds represented by formula (F11-7), and formula (F11-8), etc. Among these, compound (F11-2), compound (F11-3), compound (F11-4), Compound (F11-5), Compound (F11-6), Formula (F11-7), Formula (F11-8).

[chemical 8]

[chemical 9]

[chemical 10]

[chemical 11]

[chemical 12]

[chemical 13]

[chemical 14]

[chemical 15]

In compound (F12), Q is 4 carbon atoms that can be substituted by an alkyl group with 1 to 6 carbon atoms, an aryl group with 6 to 10 carbon atoms, or an acyloxy group with 1 to 10 carbon atoms that may have a substituent. Or 5 alkylene groups, 3 or 4 carbon number alkyleneoxy groups. The position of oxygen in the case of an alkyleneoxy group is preferably not adjacent to N. Furthermore, Q is preferably a butyl group which may be substituted with an alkyl group having 1 to 3 carbon atoms, especially a methyl group.

In compound (F12), -NR ⁷ R ⁸ is preferably -NH-C(=O)-(CH ₂ ) _m -CH ₃ (m is 0-19), -NH-C(=O)-Ph -R ¹⁰ (-Ph- represents a phenylene group, R ¹⁰ represents a hydrogen atom, a C 1-3 alkyl group or a C 1-3 alkoxy group in which a hydrogen atom may be replaced by a fluorine atom), etc.

Here, the λ _max of the compound (F12) is on the relatively long-wavelength side in the above-mentioned wavelength region, so the use of the compound (F12) can expand the transmission region in the visible wavelength range. As a compound (F12), the compound etc. which are represented by following formula (F12-1), formula (F12-2), formula (F12-3), etc. are mentioned, for example.

[chemical 16]

[chemical 17]

[chemical 18]

In compound (F13), X ¹ and X ² are independently preferably an ethylenyl group in which the hydrogen atom represented by the above (2x) may be substituted by an alkyl group having 1 to 6 carbons or an aryl group having 6 to 10 carbons . In this case, the substituent is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group. As X ¹ and X ² , specifically, -(CH ₂ ) ₂ -, -CH ₂ -C(CH 3 ) ₂ -, -CH(CH ₃ )-C(CH 3 ) 2 -, -CH(CH ₃ )-C(CH ₃ ) ₂ -, -C(CH ₃ ) ₂ -C(CH ₃ ) ₂ -etc. Y ¹ and Y ² independently include -CH ₂ -, -C(CH ₃ ) ₂ -, -CH(C ₆ H ₅ )-, -CH((CH ₂ ) _m CH ₃ )-(m 0 to 5), etc. In compound (F13), -NR ⁷ R ⁸ is preferably -NH-C(=O)-C _m H _{2m + 1} (m is 1 to 20, C _m H _{2m + 1} can be linear, branched Any one of chain and ring), -NH-C(=O)-Ph-R ¹⁰ (-Ph- means phenylene group, R ¹⁰ means hydrogen atom, alkyl group with 1 to 3 carbons, carbon alkoxy with 1 to 3 carbons, or perfluoroalkyl with 1 to 3 carbons), etc.

As a compound (F13), the compound etc. which are respectively represented by following formula (F13-1) and a formula (F13-2) are mentioned, for example.

[chemical 19]

[chemical 20]

In addition, a squarylium-based compound represented by the following formula (F2) can also be used as the near-infrared absorbing dye (A). Formula (F2) represents a compound in which none of ring A, ring B, and ring C is formed in formula (F1) (wherein, R ¹ to R ⁶ are as follows).

[chem 21]

The symbols in formula (F2) are as follows. R ¹ and R ² each independently represent a hydrogen atom, an optionally substituted alkyl or allyl group having 1 to 12 carbons, or an aryl or alkaryl group having 6 to 11 carbons. R ³ and R ⁵ each independently represent a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 6 carbon atoms. R ⁴ and R ⁶ independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl or alkoxy group with 1 to 6 carbons, an acyloxy group with 1 to 10 carbons, or -NR ⁷ R ⁸ (R ⁷ and R ⁸ are each independently a hydrogen atom, an alkyl group with 1 to 20 carbons, or -C(=O)-R ⁹ (R ⁹ is a hydrogen atom, an alkyl group with 1 to 20 carbons that may have substituents, or carbon an aryl group having 6 to 11 carbon atoms, or an alkaryl group having 7 to 18 carbon atoms which may have a substituent and may have an oxygen atom between carbon atoms).

As a compound (F2), the compound etc. which are represented by a formula (F2-1) and a formula (F2-2) are mentioned, for example.

[chem 22]

[chem 23]

Furthermore, a squarylium-based compound represented by the following formula (F3) can also be used as the near-infrared-absorbing dye (A).

[chem 24]

Compound (F1), such as compound (F11), compound (F12), and compound (F13), or compound (F2) and compound (F3) can be produced by known methods. Compound (F11) such as compound (F11-1) can be produced by the method described in US Pat. No. 5,543,086, for example. Also, compound (F12) can be produced, for example, by the method described in J. Org. Chem. 2005, 70(13), 5164-5173.

When the near-infrared absorbing dye (A) is a squarylium-based compound, a commercially available product can also be used. As a commercial item, S2098, S2084 (trade name, FEW Chemicals make) etc. are mentioned.

The near-infrared-absorbing dye (A) that is a cyanine-based compound specifically includes at least one selected from the group consisting of cyanine-based compounds represented by the following formula (F4).

[chem 25]

Wherein, the symbols in formula (F4) are as follows. R ¹¹ each independently represent an alkyl group, an alkoxy group or an alkyl group having 1 to 20 carbon atoms, or an anionic species thereof.

R ¹² and R ¹³ each independently represent a hydrogen atom or an alkyl group having 1 to 20 carbons.

Z represents PF ₆ , ClO ₄ , R ^f -SO ₂ , (R ^f -SO ₂ ) ₂ -N (R ^f represents an alkyl group with 1 to 8 carbon atoms in which at least one hydrogen atom is replaced by a fluorine atom), or BF ₄ .

R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms. N represents an integer of 1-6.

Furthermore, R ¹¹ in the compound (F4) is preferably an alkyl group having 1 to 20 carbons, and R ¹² and R ¹³ are each independently preferably a hydrogen atom or an alkyl group having 1 to 6 carbons. R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ are each independently preferably a hydrogen atom, and the number of n is preferably 1-4. The left and right structures separated by n repeating units may be different, but are preferably the same structure.

As the compound (F4), more specifically, a compound represented by the following formula (F4-1), a compound represented by the following formula (F4-2), and the like can be illustrated. The anion represented by Z- is the same as Z- in (F4) above.

[chem 26]

[chem 27]

A commercial item can also be used as a near-infrared-absorbing dye (A) of a cyanine compound. As a commercial item, ADS680HO (trade name, manufactured by American Dye Inc.), S0830 (trade name, manufactured by Few Chemicals Inc.), S2137 (trade name, manufactured by Few Chemicals Inc.), and the like may, for example, be mentioned.

In addition, the phthalocyanine compounds that can be used as the near-infrared absorbing dye (A) include FB22 (trade name, manufactured by Yamada Chemical Industry Co., Ltd.), TXEX720 (trade name, manufactured by Nippon Shokubai Co., Ltd.), PC142c (trade name , manufactured by Yamada Chemical Industry Co., Ltd.) and other commercially available products.

In the present embodiment, as the near-infrared absorbing dye (A), one of a plurality of compounds selected from a plurality of compounds having a maximum absorption wavelength in the wavelength region of 650 nm to 760 nm may be used alone, or two or more of them may be used in combination. The near-infrared-absorbing dye (A) preferably contains one or two or more of the above-mentioned near-infrared-absorbing dyes (A). In addition, the near-infrared-absorbing dye (A) may contain arbitrary near-infrared-absorbing dyes as needed. When using a plurality of near-infrared-absorbing dyes as the near-infrared-absorbing dye (A), it is preferable to use these near-infrared-absorbing dyes in combination so as to exhibit a maximum absorption wavelength in the wavelength region of 650 nm to 760 nm. Furthermore, it is preferable to use near-infrared absorbing dyes in combination such that in the absorption curve, the absorption in the visible light region is small, the slope of the λ _max absorption peak is steep on the visible light side, and the slope is gentle on the long wavelength side. Also, a near-infrared-absorbing dye selected from a plurality of compounds having a maximum absorption wavelength outside the wavelength range of 650 nm to 760 nm can be used in combination with the near-infrared-absorbing dye (A).

(inorganic materials) As the inorganic material (B), an inorganic material having a refractive index of 1.38 to 2.20 at a wavelength of 500 nm is preferable.

Specific examples of the inorganic material (B) include silica, alumina, magnesium fluoride, sodium fluoride, lanthanum fluoride, lithium fluoride, calcium fluoride, barium fluoride, lanthanum oxide, Cerium, germanium oxide, indium oxide, magnesium oxide, zirconia, tantalum oxide, yttrium oxide, tungsten oxide, zinc oxide, ITO, materials obtained by changing the valence of these compounds, and any one of them as the main component Composite materials obtained by mixing and adjusting the refractive index, etc. Among them, the smaller the difference in refractive index with the transparent substrate 1, the easier it is to deliberately adjust the spectral characteristics, and from the viewpoint of ensuring practical reliability, the inorganic material is preferably selected from silicon dioxide, One or more of alumina and magnesium fluoride. Also, when using an inorganic material with a refractive index of 1.38 to 2.20 at a wavelength of 500 nm as the inorganic material (B), one of these inorganic materials can be used alone as long as the overall refractive index is within this range. It is also possible to mix and use 2 or more types.

In the filter 10, the matrix material for dispersing the near-infrared absorbing pigment (A) is an inorganic material, so it is considered that the number of hydroxyl groups is less than that of a resin matrix material, and it is possible to suppress near-infrared absorption caused by sunlight or indoor light. Photooxidation of infrared absorbing pigment (A). Therefore, the optical filter 10 can exhibit excellent light resistance and near-infrared shielding properties.

The film thickness of the first light-absorbing layer 2 is not particularly limited, and can be appropriately determined according to the application, that is, the arrangement space in the device to be used, the required absorption characteristics, and the like. The film thickness of the first light-absorbing layer 2 is preferably 0.1 μm to 100 μm. When the film thickness is less than 0.1 μm, there is a possibility that the near-infrared absorption capability cannot be sufficiently expressed. Moreover, when the film thickness exceeds 100 μm, the flatness of the film may be lowered, which may cause unevenness in absorption rate. The film thickness is more preferably 0.2 μm to 0.7 μm. Within this range, sufficient near-infrared absorption capability can be obtained. In addition, in this specification, a film thickness means a physical film thickness.

The first light-absorbing layer 2 may optionally contain optional components other than the near-infrared-absorbing dye (A) and the inorganic material (B) within the range that does not inhibit the effects of the present invention. Specific examples of optional components include near-infrared or infrared absorbers, color tone correction pigments, ultraviolet absorbers, leveling agents, antistatic agents, heat stabilizers, light stabilizers, and antioxidants. The content of these optional components in the first light-absorbing layer 2 is preferably 15 parts by mass or less, respectively, with respect to 100 parts by mass of the inorganic material (B).

As an optional component, it is preferable to contain an ultraviolet absorber among the above-mentioned arbitrary components. The first light-absorbing layer 2 can exhibit both the function of absorbing near-infrared rays and the function of absorbing ultraviolet rays by containing an ultraviolet absorber.

Examples of the ultraviolet absorber include ultraviolet absorbing pigments (C ), inorganic UV absorbers, etc. The ultraviolet absorbing agent is preferably the above-mentioned ultraviolet absorbing pigment (C) in terms of high absorbance, efficient absorption of the required ultraviolet band, and high steepness, so that the loss of transmittance in the visible band is not easy to occur.

As the ultraviolet absorbing dye (C), merocyanine-based compounds and benzoxazole-based compounds are preferable among the above.

The ultraviolet-absorbing dye (C) which is a merocyanine-based compound is specifically preferably a merocyanine-based compound represented by the following formula (U1).

[chem 28]

The symbols in formula (U1) are as follows. Y represents a methylene group or an oxygen atom substituted by R ⁶ and R ⁷ . R ¹ represents a valent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent. R ² to R ⁷ each independently represent a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 10 carbons. X represents any one of the divalent groups represented by the following formulas (X1) to (X5) (wherein R ⁸ and R ⁹ each independently represent a valent hydrocarbon group with a carbon number of 1 to 12 that may have a substituent, R ¹⁰ to R ¹⁹ each independently represent a hydrogen atom, or a C1-C12 valent hydrocarbon group which may have a substituent).

[chem 29]

In formula (U1), it is preferred that R ¹ , R ⁸ and R ⁹ are each independently an alkyl group with 1 to 6 carbon atoms that may be substituted by a part of a hydrogen atom or a phenyl group, and R ² to R ⁷ and R ¹⁰ to R ¹⁹ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbons.

In formula (U1), preferably R ¹ , R ⁸ and R ⁹ are each independently an alkyl group with 1 to 6 carbons, and R ² to R ⁷ and R ¹⁰ to R ¹⁹ are each independently a hydrogen atom or a carbon number 1 to 6 alkyl groups.

As the compound (U1), for example, the following formula (U1-1), formula (U1-2), formula (U1-3), (U1-4), formula (U1-5), formula (U1- 6) Compounds etc. represented respectively.

[chem 30]

[chem 31]

[chem 32]

[chem 33]

[chem 34]

[chem 35]

As the ultraviolet absorbing dye (C) which is a benzoxazole type compound, the compound etc. which are represented by following formula (U2-1) are mentioned, for example.

[chem 36]

As an inorganic type ultraviolet absorber, zinc oxide, titanium oxide, cerium oxide, zirconium oxide, mica, kaolin, sericite etc. are mentioned, for example.

[Optical properties] The optical filter 10 preferably has the following characteristics (a-1) to (a-4). (a-1) The average transmittance of light at a wavelength of 440 nm to 500 nm at an incident angle of 0° is 75% or more. (a-2) The average transmittance of light at a wavelength of 500 nm to 600 nm at an incident angle of 0° is 75% or more. (a-3) The difference between the wavelength on the short-wavelength side and the wavelength on the long-wavelength side when the transmittance in the infrared wavelength range is 50% at an incident angle of light of 0° is 35 nm or more. (a-4) The transmittance of light at a wavelength of 700 nm at an incident angle of 0° is 65% or less.

The transmittance is a value measured by a UV-Vis-NIR spectrophotometer. In this specification, the average transmittance in a specific wavelength region means the average value of the transmittance at all wavelengths in the wavelength region. Also, when measuring the transmittance of light from a direction other than the direction perpendicular to the main surface of the sample and measuring the transmittance, the straight line representing the incident direction of light is compared to the line perpendicular to the main surface. The angle formed is called the angle of incidence. In addition, unless otherwise specified, the light transmittance refers to the ratio of the light incident from the direction perpendicular to the main surface of the sample to the opposite side through the inside of the sample.

The optical filter 10 can exhibit excellent near-infrared shielding characteristics by having the above-mentioned characteristics (a-1) to (a-4). Therefore, the sensitivity of the solid-state imaging device can be increased.

The optical filters 40, 50, and 60 having the second light-absorbing layer 3 shown in FIGS. 4 to 6 preferably have the following characteristics (b-1) to (b-7). (b-1) Have a wavelength λ UV50% with a light transmittance of 50% in the ultraviolet wavelength region under the incident angle of light from 0° to 50°, and the above wavelength λ _{UV50% is} in the range of wavelength 350 nm to 420 nm Inside. (b-2) The difference between the wavelength λ _UV50% at an incident angle of light of 0° and the wavelength λ _UV50% at an incident angle of light of 30° is 10 nm or less. (b-3) The average transmittance of light at a wavelength of 440 nm to 500 nm at an incident angle of 0° is 75% or more. (b-4) The average transmittance of light at a wavelength of 500 nm to 600 nm at an incident angle of 0° is 75% or more. (b-5) In the infrared wavelength region, it has a wavelength λ _IR50% with a light transmittance of 50%, the above-mentioned wavelength λ _IR50% at an incident angle of light of 0°, and the above-mentioned wavelength λ at an incident angle of light of 30° The difference in _IR50% is 10 nm or less. (b-6) The average transmittance of light at a wavelength of 750 nm to 1000 nm at an incident angle of 0° is 90% or less. (b-7) In the infrared wavelength region, there is a wavelength _λIR20% with a light transmittance of 20%, the above-mentioned wavelength _λIR20% at an incident angle of light of 0°, and the above-mentioned wavelength λ at an incident angle of light of 30° The difference in _IR20% is 5 nm or less.

The filters 40 , 50 , and 60 having the second light-absorbing layer 3 can exhibit excellent near-infrared ray shielding properties and ultraviolet ray shielding properties by having the above-mentioned properties (b-1) to (b-7). Therefore, the color reproducibility of the solid-state imaging device can be improved, and noise at the time of shooting, that is, flicker or ghosting can be suppressed.

(variation example) Modification examples of the optical filter 10 will be described with reference to FIGS. 2 to 6 . Fig. 2 is a schematic cross-sectional view of a first modification example of an optical filter according to an embodiment of the present invention. Fig. 3 is a schematic cross-sectional view of a second modification example of an optical filter according to an embodiment of the present invention. Fig. 4 is a schematic cross-sectional view of a third modification example of an optical filter according to an embodiment of the present invention. Fig. 5 is a schematic cross-sectional view of a fourth modification example of an optical filter according to an embodiment of the present invention. Fig. 6 is a schematic cross-sectional view of a fifth modification example of an optical filter according to an embodiment of the present invention.

As shown in FIG. 2 , the first light-absorbing layer 2 may have an inorganic layer 21 made of an inorganic material (B) and a dye layer 22 made of a near-infrared absorbing dye (A). Furthermore, the interface between the inorganic layer 21 and the pigment layer 22 may be one that does not clearly contain the other of the inorganic material (B) and the near-infrared-absorbing pigment (A), or may be an interface between the inorganic material (B) and the near-infrared-absorbing pigment ( A) Mixed parts. 2 shows an example of lamination in the order of transparent substrate 1 , inorganic layer 21 , and pigment layer 22 , but the order of transparent substrate 1 , pigment layer 22 , and inorganic layer 21 may also be laminated. In addition, as shown in FIG. 3 , a plurality of inorganic layers 21 and pigment layers 22 may be laminated alternately. In the example shown in FIG. 3, the inorganic layer 21 and the pigment layer 22 may be alternately laminated in reverse order.

As shown in FIG. 4 , the optical filter 40 may have the second light-absorbing layer 3 on one main surface (first main surface) side of the transparent substrate 1 . In the example shown in FIG. 4, the transparent substrate 1, the first light-absorbing layer 2, and the second light-absorbing layer 3 are stacked in the order of the layers. However, as shown in FIG. , The sequential lamination of the second light-absorbing layer 3 and the first light-absorbing layer 2 . Also, as shown in FIG. 6, the filter 60 may also be provided with a first light-absorbing layer on the first main surface side of the transparent substrate 1, and a second light-absorbing layer may be provided on the second main surface side of the transparent substrate 1. 3.

The second light-absorbing layer 3 has an ultraviolet-absorbing dye (C) having a maximum absorption wavelength at a wavelength of 300 nm to 430 nm, and a matrix material. As the ultraviolet absorbing dye (C), specifically, the same ultraviolet absorbing dye (C) as in the case of the optical filter 10 shown in FIG. 1 above can be applied.

Regarding the λ _max of the ultraviolet-absorbing pigment (C), a solution obtained by dissolving the ultraviolet-absorbing pigment (C) in methylene chloride can be used, for example, using a UV-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation, model: V770) The measurement is performed to obtain an absorption curve, and λ _max of the above-mentioned ultraviolet absorbing dye (C) is detected from the absorption curve.

The ultraviolet absorbing pigment (C) has a maximum absorption wavelength in the wavelength region of 300 nm to 430 nm, thereby imparting an excellent ability to absorb light in the ultraviolet wavelength region (300 nm to 430 nm) to the filter 10 .

The matrix material can be an inorganic material or a resin. As the inorganic material, specifically, the same inorganic material (B) as in the case of the optical filter 10 shown in FIG. 1 above can be applied.

The resin is preferably a resin with a refractive index of 1.45 or higher. The refractive index is more preferably at least 1.5, particularly preferably at least 1.6. The upper limit of the refractive index of the resin is not limited, but it is preferably about 1.72 in terms of ease of acquisition and the like.

As the resin, specifically, acrylic resin, epoxy resin, ene-thiol resin, polycarbonate resin, polyether resin, polyarylate resin, polyresin, polyether resin, polyparaffin Phenylene resins, polyaryl ether phosphine oxide resins, polyimide resins, polyamideimide resins, polyolefin resins, cyclic olefin resins, and polyester resins. Among these resins, one type may be used alone, or two or more types may be used in combination. Moreover, when using the resin whose refractive index is 1.45 or more, as long as the whole refractive index is 1.45 or more, you may use it individually from these resins, and may mix and use 2 or more types.

Among the above, polyamide is preferable from the viewpoint of high solubility of the ultraviolet absorbing dye (C) and high glass transition temperature, and the viewpoint of suppressing thermal movement of the ultraviolet absorbing dye (C) and improving heat resistance. Imine resin, polyester resin, polycarbonate resin.

Furthermore, in the optical filters 10, 20, 30, 40, 50, and 60 of this embodiment, a protective layer may be provided on the surface of the first light-absorbing layer 2 or the second light-absorbing layer 3 (the surface in contact with the atmosphere). In the example shown in FIG. 6 , a protective layer may be provided on both the surface of the first light-absorbing layer 2 and the surface of the second light-absorbing layer 3 . Regarding the protective layer, by being provided on the surface of the first light-absorbing layer 2 or the second light-absorbing layer 3, the light resistance of the filter can be improved by shielding light of a specific wavelength or moisture reaching the light-absorbing layer .

The protective layer is not particularly limited, and can be configured as an anti-reflective film, a reflective film that reflects light in a specific wavelength range, a selective wavelength shielding film that controls the transmission and shielding of light in a specific wavelength range, and a radiation shielding that shields radiation such as alpha rays. film etc. The protective layer preferably has at least one optical characteristic of suppressing reflection of visible light, optical characteristic of reflecting ultraviolet rays, and optical characteristic of reflecting infrared rays. Specifically, for example, it may have at least one of a visible light antireflective film that suppresses reflection of visible light, an ultraviolet reflective film that reflects ultraviolet rays, and an infrared reflective film that reflects infrared rays. As a protective layer having such optical properties, a dielectric multilayer film obtained by laminating a plurality of two or more dielectric films having different refractive indices can be exemplified.

As the material constituting the protective layer, for example, silicon dioxide, aluminum oxide, a composite material mainly composed of these, etc. may be mentioned. The protective layer provided on the surface of the first light-absorbing layer preferably contains the same material as the inorganic material (B). Moreover, it is preferable that the protective layer provided on the surface of the 2nd light-absorbing layer consists of the same material as a host material. Thereby, the adhesive force between each light absorbing layer and the protective layer is high, and the two are not easy to be peeled off. The protective layer may be one layer or a plurality of layers made of different materials.

The film thickness of the protective layer is preferably 0.01 μm to 10 μm, more preferably 0.1 μm to 5 μm, and is preferably relatively thin from the viewpoint of thinning the optical filter. Furthermore, when the protective layer includes a plurality of layers, the total physical film thickness of the plurality of layers is regarded as the film thickness of the protective layer.

(Manufacturing method) Regarding the manufacturing method of the optical filter 10, for example, using a vacuum evaporation method, the near-infrared absorbing pigment (A) is heated by resistance heating, and the inorganic material (B) is heated by an electron beam (EB). The first light-absorbing layer 2 is formed on the substrate 1 . In the case of the filter 10 having the first light-absorbing layer 2 containing the near-infrared-absorbing dye (A) and the ultraviolet-absorbing dye (C), for example, the near-infrared-absorbing dye (A) and the ultraviolet-absorbing dye (C) are mixed Then, heating is performed by resistance heating. By using the vacuum evaporation method, the concentration of the near-infrared-absorbing pigment (A) contained in the first light-absorbing layer 2 can be made higher than that of the wet film-forming process, so that a more excellent near-infrared ray can be obtained. Filters with masking properties.

In the case of the optical filter 20 shown in FIG. 2, for example, the inorganic material (B) is heated by an electron beam (EB), and after the inorganic layer 21 is formed on the transparent substrate 1, the near-infrared rays are heated by resistance heating. The absorbing dye (A) is heated to form a dye layer 22 on the inorganic layer 21 . In the case of the optical filter 30 shown in FIG. 3, the above operation is repeated to form a plurality of laminated structures.

For the optical filters 40 , 50 , and 60 shown in FIGS. 4 to 6 , for example, the vacuum evaporation method described above can also be applied. As a method of producing the second light absorbing layer 3 , when using an inorganic material as the host material, for example, it can be formed using a vacuum evaporation method, and when using a resin, for example, it can be formed using the following method. It can be produced by dispersing and dissolving the ultraviolet absorbing pigment (C) and resin (B) in a solvent to prepare a coating liquid, and applying the coating liquid on the transparent substrate 1 or the first light The absorbent layer 2 is allowed to dry and then hardened if necessary.

In the case of providing a protective layer, for example, a vacuum film-forming process such as CVD (chemical vapor deposition, chemical vapor deposition) method, sputtering method, vacuum evaporation method, spray method, dipping method, etc. can be used for its formation. Wet film forming process, etc.

Above, the embodiments of the present invention have been described by taking the optical filters 10, 20, 30, 40, 50, and 60 shown in FIGS. 1 to 6 as examples, but the optical filters are not limited thereto. The configuration can be appropriately changed as necessary within a range that does not violate the spirit of the present invention. For example, either one of the optical filters may be provided with a reflective film that reflects light in a specific wavelength region, or a selective wavelength shielding film that controls transmission and shielding of light in a specific wavelength region.

Filters 10, 20, 30, 40, 50, and 60 can be used as cameras for smartphones, digital still cameras, digital video cameras, surveillance cameras, car cameras, web cameras, etc., or for automatic exposure Near-infrared filters for gauges, near-infrared filters for PDP (Plasma Display Panel, plasma display), etc. In addition, the optical filter can be applied in the form of an optical filter having two transmission bands of a part of wavelengths of visible light and near-infrared rays (for example, only light with a wavelength of 850 nm or 940 nm), and cut off the wavelengths outside these transmission bands. Light. The optical filter of the present invention is suitable for solid-state imaging devices such as cameras mounted on smartphones, digital still cameras, digital video cameras, surveillance cameras, vehicle-mounted cameras, and network cameras. For example, the optical filter is arranged between imaging lenses and between solid-state imaging elements. [Example]

Next, examples of the present invention will be described. The present invention is not limited by the embodiments and examples described below. In the following description, examples 1 to 3 and example 9 are examples, and example 4 is a comparative example. In addition, Examples 5 to 8 are reference examples.

Optical filters of Examples 1 to 9 having the configurations shown in Table 1 and Table 2 were fabricated. Hereinafter, Examples 1 to 9 will be described in detail.

(Example 1) A flat glass plate (D263, manufactured by Schott Co., Ltd.) having a length of 50 mm, a width of 50 mm, and a thickness of 0.3 mm was used as a transparent base material. Magnesium fluoride (MgF ₂ ) was used as the host material, and the compound (F11-7) (molecular weight 766.54, maximum absorption wavelength in methylene chloride solution was 706 nm, manufactured by Tokyo Chemical Industry Co., Ltd., product name: UVITEX OB) was used as the near-infrared ray The absorbing pigment is formed into a film on a glass plate in a mixed state using a vacuum evaporation device to form a light absorbing layer. Compound (F11-7) was synthesized based on International Publication (WO2014/088063). The light-absorbing layer is properly adjusted so that the film thickness is between 200 nm and 700 nm. On the surface of the obtained light-absorbing layer, silicon oxide (SiO ₂ ) was deposited using a vacuum deposition apparatus so that the film thickness became 100 nm or more to form a protective layer, thereby obtaining the optical filter of Example 1.

(Example 2) The optical filter of Example 2 was obtained in the same manner as in Example 1 except that SiO ₂ was used as the host material in Example 1.

(Example 3) Except using the compound (F11-8) (molecular weight 850.63, the maximum absorption wavelength in dichloromethane solution is 714 nm) as the near-infrared absorbing pigment in Example 1, the filter of Example 3 was obtained in the same way as Example 1 device.

(Example 4) To a solution obtained by dissolving polyimide (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name: C-3G30G) in an organic solvent, the compound ( F11-7) After serving as a near-infrared absorbing dye, it was stirred and dissolved at room temperature to obtain a coating liquid. The obtained coating solution was applied by spin coating on a flat glass plate (D263; manufactured by Schott Co., Ltd.) of length: 50 mm, width: 50 mm, and thickness: 0.21 mm as a transparent substrate. , heated and dried to remove the organic solvent, and formed a light-absorbing layer with a film thickness of 1.11 μm, thereby obtaining the optical filter of Example 4.

(Example ₅ ) Use SiO as the host material in Example 1, use compound (F11-8) (molecular weight 850.63, maximum absorption wavelength in dichloromethane solution is 714 nm) as the near-infrared ray absorbing pigment in Example 1, except Otherwise, the optical filter of Example 5 was obtained in the same manner as in Example 1.

(Example 6) Using a flat glass plate (D263, manufactured by Schott Co., Ltd.) of length: 50 mm, width: 50 mm, and thickness: 0.3 mm as a transparent substrate, aluminum oxide (Al ₂ O ₃ ) was used as a base material, An inorganic layer with a film thickness of 10 nm was formed on a glass plate by vacuum evaporation. Then, on the surface of the obtained inorganic layer, a compound (F11-7) (molecular weight 766.54, maximum absorption wavelength in dichloromethane solution: 706 nm) was used as a near-infrared absorbing pigment to form a thick film by vacuum evaporation. 13 nm ~ 20 nm pigment layer. The formation of the above-mentioned inorganic layer was repeated 6 times, and the formation of the dye layer was repeated 5 times, and the inorganic layer and the dye layer were alternately laminated in units of one layer to form a light-absorbing layer including a total of 11 layers. The outermost surface of the light-absorbing layer is an inorganic layer with a film thickness of 10 nm formed by vacuum evaporation using aluminum oxide (Al ₂ O ₃ ), and this inorganic layer is a protective layer. Thus, the optical filter of Example 6 was obtained.

(Example 7) The optical filter of Example 7 was obtained in the same manner as in Example 6, except that SiO ₂ was used as the host material in Example 6, and the film thickness of SiO 2 was 46 nm to 53 nm. In Example 7, the outermost surface of the light-absorbing layer is an inorganic layer with a film thickness of 53 nm formed by vacuum evaporation using SiO ₂ , and the inorganic layer is a protective layer.

(Example 8) The optical filter of Example 8 was obtained in the same manner as in Example 1 except that SiO ₂ was used as the host material in Example 1 and no protective layer was provided.

(Example 9) In addition to using magnesium fluoride (MgF ₂ , 100 nm) instead of silicon oxide as the protective layer on the surface of the light-absorbing layer in Example 1, the light filter of Example 9 was obtained in the same manner as Example 1 device.

[Determination of spectral transmittance] For the obtained optical filters of Examples 1 to 9, a UV-Vis-NIR spectrophotometer (manufactured by JASCO Corporation, model: V770) was used to measure the transmittance at an incident angle of 0° to obtain a spectral transmittance curve. The spectral transmittance curve of the optical filter of Example 1 is shown in Figure 7, the spectral transmittance curve of the optical filter of Example 2 is shown in Figure 8, and the spectral transmittance curve of the optical filter of Example 3 is shown in Figure 9 , the spectral transmittance curve of the optical filter of Example 4 is shown in Figure 10, the spectral transmittance curve of the optical filter of Example 5 is shown in Figure 11, and the spectral transmittance of the optical filter of Example 6 is shown in Figure 12 Curve, the spectral transmittance curve of the optical filter of example 7 is shown in Fig. 13, the spectral transmittance curve of the optical filter of example 8 is shown in Fig. 14, the spectral transmittance of the optical filter of example 9 is shown in Fig. 15 rate curve. As shown in FIGS. 7 to 15 , it can be seen that the optical filters of Examples 1 to 9 are optical filters with low transmittance of light near a wavelength of 700 nm and have near-infrared shielding characteristics.

[Evaluation of Light Resistance] A light resistance test was performed on the obtained optical filters of Examples 1 to 4 and Example 9, and the light resistance was evaluated. In the light resistance test, the filter was irradiated with light under the following conditions using Super Xenon Weather Meter SX75 (manufactured by Suga Test Instruments Co., Ltd.). (Irradiation conditions) Wavelength: 300-2450 nm Temperature: 40°C Humidity: 50% RT Cumulative light intensity: 87.2 kw·hour/ ^m2 After light irradiation, measure the transmittance at an incident angle of 0° to obtain a spectral transmittance curve. The spectral transmittance curve before and after the light fastness test of the optical filter of example 1 is shown in Fig. 7, the spectral transmittance curve before and after the light fastness test of the optical filter of example 2 is shown in Fig. 8, and the example is shown in Fig. 9 The spectral transmittance curve before and after the light fastness test of the optical filter of 3, the spectral transmittance curve before and after the light fastness test of the optical filter of example 4 is shown in Fig. 10, and the spectral transmittance curve of the optical filter of example 9 is shown in Fig. 15 Spectral transmittance curves before and after the light fastness test.

From the spectral transmittance curve before and after light irradiation, obtain the minimum transmittance under light with a wavelength of 500 nm to 800 nm before and after irradiation, and calculate the variation according to the following formula. Minimum transmittance variation [%] = (minimum transmittance of light with a wavelength of 500 nm to 800 nm before irradiation) - (minimum transmittance of light with a wavelength of 500 nm to 800 nm after irradiation) The evaluation of the light fastness was set as A when the minimum transmittance variation [%] was 10% or less, and as B when it exceeded 10%, as shown in Table 1, and A was regarded as a pass.

[Table 1] example 1 Example 2 Example 3 Example 4 Example 9 transparent substrate Glass (D263) Glass (D263) Glass (D263) Glass (D263) Glass (D263) light absorbing layer Matrix material _MgF2 SiO _{2 MgF2} polyimide _MgF2 Near Infrared Absorbing Pigments Compound (F11-7) Compound (F11-7) Compound (F11-8) Compound (F11-7) Compound (F11-7) Maximum absorption wavelength of near-infrared absorbing pigment [nm] 706 706 714 706 706 Molecular weight of near-infrared absorbing pigment 766.54 766.54 850.63 766.54 766.54 The protective layer SiO ₂ SiO ₂ SiO ₂ SiO _{2 MgF2} Lightfastness A A A B A

[Table 2] Example 5 Example 6 Example 7 Example 8 transparent substrate Glass (D263) Glass (D263) Glass (D263) Glass (D263) light absorbing layer Matrix material SiO ₂ Al ₂ O ₃ SiO ₂ SiO ₂ Near Infrared Absorbing Pigments Compound (F11-8) Compound (F11-7) Compound (F11-7) Compound (F11-7) Maximum absorption wavelength of near-infrared absorbing pigment [nm] 714 706 706 706 Molecular weight of near-infrared absorbing pigment 850.63 766.54 766.54 766.54

As shown in Table 1, it can be seen that the optical filters of Examples 1 to 3 and Example 9 using inorganic materials as host materials are optical filters having good light resistance. Since the base material is an inorganic material, it is considered that the photooxidation of the near-infrared absorbing dye (A) caused by light is suppressed due to fewer hydroxyl groups than when the base material is a resin.

(Aspects of the present invention) The present invention includes the following aspects. ＜Form 1＞ A kind of optical filter, it has the transparent base material that has the 1st main surface, and the first light-absorbing layer provided on the first main surface side of the transparent substrate, and The first light-absorbing layer includes a near-infrared absorbing dye and an inorganic material, The near-infrared absorbing dye has a maximum absorption wavelength at a wavelength of 650 nm to 760 nm, and has a molecular weight of 2000 or less. ＜Model 2＞ The optical filter according to aspect 1, wherein the first light-absorbing layer is formed by mixing the near-infrared absorbing dye and the inorganic material. ＜Model 3＞ The optical filter according to aspect 2, wherein the concentration of the near-infrared absorbing dye differs in the direction perpendicular to the first main surface. ＜Form 4＞ The optical filter according to aspect 1, wherein the first light-absorbing layer has a dye layer including the near-infrared absorbing dye, and an inorganic layer including the inorganic material. ＜Aspect 5＞ The optical filter according to any one of aspects 1 to 4 has the following characteristics. (a-1) The average transmittance of light at a wavelength of 440 nm to 500 nm at an incident angle of 0° is 75% or more. (a-2) The average transmittance of light at a wavelength of 500 nm to 600 nm at an incident angle of 0° is 75% or more. (a-3) The difference between the wavelength on the short-wavelength side and the wavelength on the long-wavelength side when the transmittance in the infrared wavelength range is 50% at an incident angle of light of 0° is 35 nm or more. (a-4) The transmittance of light at a wavelength of 700 nm at an incident angle of 0° is 65% or less. ＜Form 6＞ The optical filter according to any one of aspects 1 to 5, wherein the near-infrared absorbing pigment is at least one selected from the group consisting of squarylium-based compounds, phthalocyanine-based compounds, and cyanine-based compounds . ＜Aspect 7＞ The optical filter according to aspect 6, wherein the squarylium-based compound has a structure represented by the following formula (F1).

其中，式(F1)中之符號如下所述。R ⁴及R ⁶分別獨立地表示氫原子、鹵素原子、羥基、碳數1～20之烷基、碳數1～20之烷氧基、碳數1～10之醯氧基、碳數6～11之芳基、可具有取代基且可於碳原子間具有氧原子之碳數7～18之烷芳基、-NR ⁷R ⁸(R ⁷及R ⁸分別獨立地表示氫原子、碳數1～20之烷基、-C(=O)-R ⁹(R ⁹為氫原子、鹵素原子、羥基、可具有取代基且可於碳原子間包含不飽和鍵、氧原子、飽和或不飽和環結構之碳數1～25之烴基)、-NHR ¹⁰、或-SO ₂-R ¹⁰(R ¹⁰分別為1個以上之氫原子可被取代為鹵素原子、羥基、羧基、磺基、或氰基且可於碳原子間包含不飽和鍵、氧原子、飽和或不飽和環結構之碳數1～25之烴基))、或者下述式(S)所表示之基(R ⁴¹、R ⁴²獨立地表示氫原子、鹵素原子、或者碳數1～10之烷基或碳數1～10之烷氧基，k為2或3)。 [chemical 1]

Wherein, the symbols in the formula (F1) are as follows. R ⁴ and R ⁶ independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group with 1 to 20 carbons, an alkoxy group with 1 to 20 carbons, an acyloxy group with 1 to 10 carbons, an acyloxy group with 6 to 20 carbons, 11 aryl groups, alkaryl groups with 7 to 18 carbons which may have substituents and may have an oxygen atom between carbon atoms, -NR ⁷ R ⁸ (R ⁷ and R ⁸ each independently represent a hydrogen atom, carbon number 1 ~20 alkyl groups, -C(=O) ^-R9 ( ^R9 is a hydrogen atom, a halogen atom, a hydroxyl group, may have a substituent and may contain an unsaturated bond between carbon atoms, an oxygen atom, a saturated or unsaturated ring Hydrocarbon group with 1 to 25 carbon atoms in the structure), -NHR ¹⁰ , or -SO ₂ -R ¹⁰ (R ¹⁰ is one or more hydrogen atoms, which can be replaced by halogen atoms, hydroxyl, carboxyl, sulfo, or cyano And may contain unsaturated bonds between carbon atoms, oxygen atoms, hydrocarbon groups with 1 to 25 carbon atoms in saturated or unsaturated ring structures)), or groups represented by the following formula (S) (R ⁴¹ , R ⁴² independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 10 carbons or an alkoxy group having 1 to 10 carbons, and k is 2 or 3).

R ¹與R ²、R ²與R ⁵、及R ¹與R ³可相互連結而與氮原子一起形成員數為5或6之各個雜環A、雜環B、及雜環C。 ＜態樣8＞ 如態樣1至7中任一項所記載之濾光器，其中上述無機材料之波長500 nm下之折射率為1.38～2.20。 ＜態樣9＞ 如態樣8所記載之濾光器，其中上述無機材料為選自由二氧化矽、氧化鋁、及氟化鎂所組成之群中之至少一種。 ＜態樣10＞ 如態樣1至9中任一項所記載之濾光器，其於上述第1光吸收層之表面具備保護層。 ＜態樣11＞ 如態樣10所記載之濾光器，其中設置於上述第1光吸收層之表面之上述保護層包含與上述無機材料相同之材料。 ＜態樣12＞ 如態樣10或11所記載之濾光器，其中設置於上述第1光吸收層之表面之上述保護層具有抑制可見光反射之光學特性、反射紫外線之光學特性、及反射紅外線之光學特性中之至少一種光學特性。 ＜態樣13＞ 如態樣1至12中任一項所記載之濾光器，其於上述透明基材之上述第1主面側具備第2光吸收層，且 第2光吸收層包含紫外線吸收色素、及基質材料， 上述紫外線吸收色素於波長300 nm～430 nm處具有最大吸收波長。 ＜態樣14＞ 如態樣13所記載之濾光器，其中上述基質材料為選自由二氧化矽、氧化鋁、氟化鎂、聚醯亞胺樹脂、聚酯樹脂、及聚碳酸酯樹脂所組成之群中之任一種。 ＜態樣15＞ 如態樣13或14所記載之濾光器，其中上述紫外線吸收色素為選自由三𠯤系化合物、吲哚系化合物、甲亞胺系化合物、苯并三唑系化合物、部花青系化合物、及苯并㗁唑系化合物所組成之群中之至少一種。 ＜態樣16＞ 如態樣15所記載之濾光器，其中上述紫外線吸收色素包含下述式(U1)所表示之部花青系化合物。 [Chem 2]

R ¹ and R ² , R ² and R ⁵ , and R ¹ and R ³ may be linked together to form heterocycle A, heterocycle B, and heterocycle C each having 5 or 6 members together with a nitrogen atom. <Aspect 8> The optical filter according to any one of aspects 1 to 7, wherein the refractive index of the above-mentioned inorganic material at a wavelength of 500 nm is 1.38 to 2.20. <Aspect 9> The optical filter according to Aspect 8, wherein the inorganic material is at least one selected from the group consisting of silicon dioxide, aluminum oxide, and magnesium fluoride. <Aspect 10> The optical filter according to any one of Aspects 1 to 9, which is provided with a protective layer on the surface of the first light-absorbing layer. <Aspect 11> In the optical filter according to Aspect 10, the protective layer provided on the surface of the first light-absorbing layer contains the same material as the inorganic material. <Aspect 12> The optical filter according to Aspect 10 or 11, wherein the protective layer provided on the surface of the first light-absorbing layer has optical properties of suppressing reflection of visible light, optical properties of reflecting ultraviolet rays, and reflecting infrared rays At least one optical characteristic among the optical characteristics. <Aspect 13> The optical filter according to any one of Aspects 1 to 12, which is provided with a second light-absorbing layer on the first main surface side of the above-mentioned transparent substrate, and the second light-absorbing layer contains ultraviolet rays. The absorbing pigment and the matrix material, the above-mentioned ultraviolet absorbing pigment has a maximum absorption wavelength at a wavelength of 300 nm to 430 nm. <Aspect 14> The optical filter according to Aspect 13, wherein the above-mentioned matrix material is selected from silicon dioxide, alumina, magnesium fluoride, polyimide resin, polyester resin, and polycarbonate resin. Any one of the group formed. <Aspect 15> The optical filter according to Aspect 13 or 14, wherein the above-mentioned ultraviolet absorbing pigment is selected from the group consisting of trioxane-based compounds, indole-based compounds, methimine-based compounds, benzotriazole-based compounds, moiety At least one of the group consisting of cyanine-based compounds and benzoxazole-based compounds. <Aspect 16> The optical filter according to Aspect 15, wherein the ultraviolet absorbing dye contains a merocyanine compound represented by the following formula (U1).

其中，式(U1)中之符號如下所述。 [Chem 3]

Wherein, the symbols in formula (U1) are as follows.

Y represents a methylene group or an oxygen atom substituted by R ⁶ and R ⁷ .

R ¹ represents a valent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent. R ² to R ⁷ each independently represent a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 10 carbons.

X represents any one of the divalent groups represented by the following formulas (X1) to (X5) (wherein R ⁸ and R ⁹ each independently represent a valent hydrocarbon group with a carbon number of 1 to 12 that may have a substituent, R ¹⁰ to R ¹⁹ each independently represent a hydrogen atom, or a C1-C12 valent hydrocarbon group which may have a substituent).

＜態樣17＞ 如態樣16所記載之濾光器，其中於式(U1)中，R ¹、R ⁸及R ⁹分別獨立地為氫原子之一部分可被取代為環烷基或苯基之碳數1～6之烷基，R ²～R ⁷及R ¹⁰～R ¹⁹分別獨立地為氫原子、或碳數1～6之烷基。 ＜態樣18＞ 如態樣16所記載之濾光器，其中於式(U1)中，R ¹、R ⁸及R ⁹分別獨立地為碳數1～6之烷基，R ²～R ⁷及R ¹⁰～R ¹⁹分別獨立地為氫原子或碳數1～6之烷基。 ＜態樣19＞ 如態樣15所記載之濾光器，其中上述紫外線吸收色素為苯并㗁唑系化合物。 ＜態樣20＞ 如態樣13至19中任一項所記載之濾光器，其於上述第2光吸收層之表面具備保護層。 ＜態樣21＞ 如態樣20所記載之濾光器，其中於上述第2光吸收層之表面所具備之上述保護層包含與上述基質材料相同之材料。 ＜態樣22＞ 如態樣20或21所記載之濾光器，其中於上述第2光吸收層之表面所具備之上述保護層具有抑制可見光反射之光學特性、反射紫外線之光學特性、及反射紅外線之光學特性中之至少一種光學特性。 ＜態樣23＞ 如態樣13至22中任一項所記載之濾光器，其具備下述特性。 (b-1)於光之入射角0°～50°下之紫外波長區域內具有使光之透過率為50%之波長λ _UV50%，上述波長λ _UV50%處於波長350 nm～420 nm之範圍內。 (b-2)光之入射角0°下之上述波長λ _UV50%、與光之入射角30°下之上述波長λ _UV50%之差為10 nm以下。 (b-3)光之入射角0°下之波長440 nm～500 nm之平均透過率為75%以上。 (b-4)光之入射角0°下之波長500 nm～600 nm之平均透過率為75%以上。 (b-5)於紅外波長區域具有使光之透過率為50%之波長λ _IR50%，光之入射角0°下之上述波長λ _IR50%、與光之入射角30°下之上述波長λ _IR50%之差為10 nm以下。 (b-6)光之入射角0°下之波長750 nm～1000 nm之平均透過率為90%以下。 (b-7)於紅外波長區域內具有光之透過率為20%時之波長λ _IR20%，光之入射角0°下之上述波長λ _IR20%、與光之入射角30°下之上述波長λ _IR20%之差為5 nm以下。 [chemical 4]

<Aspect 17> The optical filter according to Aspect 16, wherein in the formula (U1), R ¹ , R ⁸ and R ⁹ are each independently a part of a hydrogen atom and may be substituted with a cycloalkyl group or a phenyl group An alkyl group having 1 to 6 carbons, R ² to R ⁷ and R ¹⁰ to R ¹⁹ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbons. <Aspect 18> The optical filter according to Aspect 16, wherein in formula (U1), R ¹ , R ⁸ , and R ⁹ are each independently an alkyl group having 1 to 6 carbon atoms, and R ² to R ⁷ and R ¹⁰ to R ¹⁹ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbons. <Aspect 19> The optical filter according to Aspect 15, wherein the ultraviolet absorbing dye is a benzoxazole compound. <Aspect 20> The optical filter according to any one of Aspects 13 to 19, which includes a protective layer on the surface of the second light-absorbing layer. <Aspect 21> In the optical filter according to Aspect 20, the protective layer provided on the surface of the second light-absorbing layer contains the same material as the host material. <Aspect 22> The optical filter according to Aspect 20 or 21, wherein the protective layer provided on the surface of the second light-absorbing layer has optical properties for suppressing reflection of visible light, optical properties for reflecting ultraviolet rays, and reflection At least one optical characteristic among the optical characteristics of infrared rays. <Aspect 23> The optical filter according to any one of Aspects 13 to 22, which has the following characteristics. (b-1) Have a wavelength λ UV50% at which the transmittance of light is 50% in the ultraviolet wavelength region at an incident angle of light from 0° to 50°, and the above-mentioned wavelength λ _{UV50% is} in the range of wavelength 350 nm to 420 nm Inside. (b-2) The difference between the wavelength λ _UV50% at an incident angle of light of 0° and the wavelength λ _UV50% at an incident angle of light of 30° is 10 nm or less. (b-3) The average transmittance of light at a wavelength of 440 nm to 500 nm at an incident angle of 0° is 75% or more. (b-4) The average transmittance of light at a wavelength of 500 nm to 600 nm at an incident angle of 0° is 75% or more. (b-5) In the infrared wavelength region, it has a wavelength λ _IR50% at which the transmittance of light is 50%, the above-mentioned wavelength λ _IR50% at an incident angle of light of 0°, and the above-mentioned wavelength λ at an incident angle of light of 30° The difference in _IR50% is 10 nm or less. (b-6) The average transmittance of light at a wavelength of 750 nm to 1000 nm at an incident angle of 0° is 90% or less. (b-7) In the infrared wavelength region, it has the wavelength λIR20 _% when the transmittance of light is 20%, the above-mentioned wavelength _λIR20% at the incident angle of light of 0°, and the above-mentioned wavelength at the incident angle of light of 30° The difference in λ _IR20% is 5 nm or less.

This international application claims priority based on Japanese Patent Application No. 2021-121013 filed on July 21, 2021, the entire contents of which are incorporated herein by reference.

1: Transparent substrate 2: The first light absorbing layer 3: The second light absorbing layer 10: Filter 20: Filter 21: Inorganic layer 22: Pigment layer 30: Filter 40: Optical filter 50: Filter 60: Filter

Fig. 1 is a schematic cross-sectional view of an optical filter according to an embodiment of the present invention. Fig. 2 is a schematic cross-sectional view of a first modification example of an optical filter according to an embodiment of the present invention. Fig. 3 is a schematic cross-sectional view of a second modification example of an optical filter according to an embodiment of the present invention. Fig. 4 is a schematic cross-sectional view of a third modification example of an optical filter according to an embodiment of the present invention. Fig. 5 is a schematic cross-sectional view of a fourth modification example of an optical filter according to an embodiment of the present invention. Fig. 6 is a schematic cross-sectional view of a fifth modification example of an optical filter according to an embodiment of the present invention. FIG. 7 is a graph showing spectral transmittance curves before and after a light fastness test of the filter in Example 1. FIG. FIG. 8 is a graph showing spectral transmittance curves before and after a light fastness test of the filter in Example 2. FIG. Fig. 9 is a graph showing the spectral transmittance curves before and after the light fastness test of the optical filter in Example 3. FIG. 10 is a graph showing the spectral transmittance curves before and after the light fastness test of the optical filter in Example 4. FIG. FIG. 11 is a graph showing the spectral transmittance curve of the filter in Example 5. FIG. FIG. 12 is a graph showing the spectral transmittance curve of the filter in Example 6. FIG. FIG. 13 is a graph showing the spectral transmittance curve of the filter in Example 7. FIG. FIG. 14 is a graph showing the spectral transmittance curve of the filter in Example 8. FIG. Fig. 15 is a graph showing the spectral transmittance curves before and after the light fastness test of the optical filter in Example 9.

1: Transparent substrate

2: The first light absorbing layer

10: Filter

Claims (23)

A kind of optical filter, it has the transparent base material that has the 1st main surface, and the first light-absorbing layer provided on the first main surface side of the transparent substrate, and The first light-absorbing layer includes a near-infrared absorbing dye and an inorganic material, The near-infrared absorbing dye has a maximum absorption wavelength at a wavelength of 650 nm to 760 nm, and has a molecular weight of 2000 or less. The optical filter according to claim 1, wherein the first light-absorbing layer is formed by mixing the near-infrared absorbing dye and the inorganic material. The optical filter according to claim 2, wherein the concentration of the near-infrared absorbing pigment differs in the direction perpendicular to the first principal surface. The optical filter according to claim 1, wherein the first light-absorbing layer has a pigment layer comprising the near-infrared absorbing pigment, and an inorganic layer comprising the inorganic material. As the optical filter of claim 2 or 4, it has the following characteristics: (a-1) The average transmittance of light at a wavelength of 440 nm to 500 nm at an incident angle of 0° is 75% or more; (a-2) The average transmittance of light at a wavelength of 500 nm to 600 nm at an incident angle of 0° is 75% or more; (a-3) The difference between the wavelength on the short-wavelength side and the wavelength on the long-wavelength side when the transmittance in the infrared wavelength region is 50% at an incident angle of light of 0° is 35 nm or more; (a-4) The transmittance of light at a wavelength of 700 nm at an incident angle of 0° is 65% or less. The optical filter according to claim 1, wherein the near-infrared-absorbing pigment is at least one selected from the group consisting of squarylium-based compounds, phthalocyanine-based compounds, and cyanine-based compounds. The optical filter according to claim 6, wherein the squarylium-based compound has a structure represented by the following formula (F1): [Chemical 1]

Among them, the symbols in formula (F1) are as follows: R ⁴ and R ⁶ independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group with 1 to 20 carbons, an alkoxy group with 1 to 20 carbons, a carbon Acyloxy with 1 to 10 carbons, aryl with 6 to 11 carbons, alkaryl with 7 to 18 carbons which may have substituents and may have an oxygen atom between carbon atoms, -NR ⁷ R ⁸ (R ⁷ and R ⁸ each independently represent a hydrogen atom, an alkyl group with 1 to 20 carbon atoms, -C(=O)-R ⁹ (R ⁹ is a hydrogen atom, a halogen atom, a hydroxyl group, may have a substituent and may be between carbon atoms Hydrocarbon groups with 1 to 25 carbon atoms containing unsaturated bonds, oxygen atoms, saturated or unsaturated ring structures), -NHR ¹⁰ , or -SO ₂ -R ¹⁰ (where R ¹⁰ is 1 or more hydrogen atoms and can be replaced by A halogen atom, a hydroxyl group, a carboxyl group, a sulfo group, or a cyano group and may contain unsaturated bonds between carbon atoms, an oxygen atom, a saturated or unsaturated ring structure with a carbon number of 1 to 25 hydrocarbon groups)), or the following formula (S ) (R ⁴¹ and R ⁴² independently represent a hydrogen atom, a halogen atom, or an alkyl group with 1 to 10 carbons or an alkoxy group with 1 to 10 carbons, k is 2 or 3), [Chem. 2 ]

R ¹ and R ² , R ² and R ⁵ , and R ¹ and R ³ may be linked together to form heterocycle A, heterocycle B, and heterocycle C each having 5 or 6 members together with a nitrogen atom. The optical filter according to claim 7, wherein the refractive index of the above-mentioned inorganic material is 1.38-2.20 at a wavelength of 500 nm. The optical filter according to claim 8, wherein the above-mentioned inorganic material is at least one selected from the group consisting of silicon dioxide, aluminum oxide, and magnesium fluoride. The optical filter according to claim 9, which has a protective layer on the surface of the first light-absorbing layer. The optical filter according to claim 10, wherein the protective layer provided on the surface of the first light-absorbing layer contains the same material as the inorganic material. The optical filter according to claim 11, wherein the above-mentioned protective layer provided on the surface of the above-mentioned first light-absorbing layer has at least one of the optical characteristics of suppressing the reflection of visible light, the optical characteristics of reflecting ultraviolet rays, and the optical characteristics of reflecting infrared rays . The optical filter according to claim 12, which is provided with a second light-absorbing layer on the first main surface side of the transparent substrate, and The second light-absorbing layer includes an ultraviolet-absorbing pigment and a matrix material, The above-mentioned ultraviolet absorbing pigment has a maximum absorption wavelength at a wavelength of 300 nm to 430 nm. The optical filter according to claim 13, wherein the above-mentioned matrix material is any one selected from the group consisting of silicon dioxide, aluminum oxide, magnesium fluoride, polyimide resin, polyester resin, and polycarbonate resin . The optical filter of claim 14, wherein the above-mentioned ultraviolet absorbing pigment is selected from the group consisting of trioxane-based compounds, indole-based compounds, imine-based compounds, benzotriazole-based compounds, merocyanine-based compounds, and benzodiazepines At least one of the group consisting of azole compounds. The optical filter according to claim 15, wherein the above-mentioned ultraviolet absorbing pigment contains a merocyanine compound represented by the following formula (U1): [Chemical 3]

Among them, the symbols in the formula (U1) are as follows: Y represents a methylene group or an oxygen atom substituted by ^R6 and ^R7 ; ^R1 represents a carbon number of 1 to 12 that may have substituents; ^R2 ~R ⁷ each independently represent a hydrogen atom, a halogen atom, or an alkyl or alkoxy group with 1 to 10 carbons; X represents any one of the divalent groups represented by the following formulas (X1) to (X5) (wherein, R ⁸ and R ⁹ each independently represent a monovalent hydrocarbon group having 1 to 12 carbon atoms that may have a substituent, and R ¹⁰ to R ¹⁹ each independently represent a hydrogen atom, or a C 1 to 12 carbon group that may have a substituent One valent hydrocarbon group); [Chemical 4]

. The optical filter according to claim 16, wherein in the formula (U1), R ¹ , R ⁸ and R ⁹ are each independently a part of a hydrogen atom and can be substituted with a cycloalkyl group or a phenyl group with 1 to 6 carbon atoms. In the alkyl group, R ² to R ⁷ and R ¹⁰ to R ¹⁹ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbons. The optical filter according to claim 16, wherein in formula (U1), R ¹ , R ⁸ and R ⁹ are each independently an alkyl group with 1 to 6 carbons, and R ² to R ⁷ and R ¹⁰ to R ¹⁹ are respectively are independently a hydrogen atom or an alkyl group having 1 to 6 carbons. The optical filter according to claim 15, wherein the above-mentioned ultraviolet absorbing pigment is a benzoxazole compound. In the optical filter according to claim 19, a protective layer is provided on the surface of the second light absorbing layer. The optical filter according to claim 20, wherein the protective layer provided on the surface of the second light-absorbing layer is made of the same material as the host material. The optical filter according to claim 21, wherein the protective layer provided on the surface of the second light-absorbing layer has at least one optical characteristic of suppressing reflection of visible light, optical characteristic of reflecting ultraviolet rays, and optical characteristic of reflecting infrared rays characteristic. Such as the optical filter of claim 13, which has the following characteristics: (b-1) has a wavelength λ _UV50 % that makes the light transmittance 50% in the ultraviolet wavelength region under the incident angle of light from 0° to 50° , the above-mentioned wavelength λ _UV50% is within the wavelength range of 350 nm to 420 nm; (b-2) The above-mentioned wavelength λ _UV50% under the light incident angle of 0° and the above-mentioned wavelength λ _UV50% under the light incident angle of 30° The difference is less than 10 nm; (b-3) The average transmittance of the wavelength 440 nm to 500 nm at the incident angle of light of 0° is more than 75%; (b-4) The wavelength of light at the incident angle of 0° is 500 nm The average transmittance of ~600 nm is more than 75%; (b-5) In the infrared wavelength region, it has a wavelength λ _IR50% that makes the transmittance of light 50%, and the above-mentioned wavelength λ _IR50 % at an incident angle of light of 0° (b-6) The average transmittance of the wavelength 750 nm to 1000 nm at an incident angle of light of 0° is less than ₉₀ %; ( b-7) In the infrared wavelength region, it has a wavelength λ _IR20% with a light transmittance of 20%, the above-mentioned wavelength λ _IR20% at an incident angle of light of 0°, and the above-mentioned wavelength λ _IR20 at an incident angle of light of 30° _% difference is 5 nm or less.

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